In prior art business communication switching systems (also referred to as PBXs), a conference call can be set up between a plurality of telephone stations sets. However, even with a station set that has a single-line alphanumeric display, the users on the conference call can not display the names and telephone number of the other parties on that conference call. If a conferee joins a conference call after the conference call has been established, the joining conferee has no mechanism for establishing who is on the conference call except by asking each of the other conferees to give their names. Similarly, if a conferee drops off of the conference call, without stating that they are dropping off, the other conferees have no way of determining that the conferee has dropped off of the conference call.
Within the AT&T long distance telephone network, a teleconferencing service known as the Alliance Dedicated Teleconferencing Service is available. The Alliance service comprises a teleconferencing bridge connected to a 4ESS toll switch. On the Alliance service, conference calls are set up and controlled by AT&T operators who can obtain a visual display of the individuals on the conference by name and telephone number. In an attempt to improve upon the Alliance service, U.S. Pat. No. 4,796,293 discloses interposing a service computer between a coordinator of a conference call and the Alliance service. The service computer uses the same interface into the Alliance service as that of an AT&T operator terminal. The service computer takes the place of the AT&T operator and gives the coordinator an improved human interface to the Alliance service. In order to establish communication with the service computer, the coordinator is required to use a separate packet data system to establish communication between the service computer and the coordinator's computer terminal. Once this communication has been established, the coordinator has the same capability as the AT&T operator.
The problems in the prior art are (1) the lack of the capability to inspect the identity of the parties on a conference call in business communications switching systems, and (2) the need in the system disclosed by U.S. Pat. No. 4,796,293 for a separate service computer which requires interconnection via a separate packet network. Further, in the case of U.S. Pat. No. 4,796,293, the conference call must begin on a dedicated bridge for which advance reservations are required.
What is needed is a mechanism for a telephone terminal having only a single-line alphanumeric display to be able to step through the identity of each of the conferees on the conference call. In addition, the telephone terminal should control the inspection operation and should receive the identifies of the other conferees using standard telephone protocols without the necessity of having a separate packet network.